The use of computed tomography in determining developmental changes, anomalies, and trauma of the thyroid cartilage.

Recognition of injury to the hyoid bone and thyroid and cricoid cartilages is intrinsic to post-mortem examination. Due to its increasing brittleness with age the thyroid cartilage is particularly susceptible to injury following neck trauma, although there is inconsistency in the patterns of injury reported. In this study computed tomography scans of the head and neck of 431 deceased persons (235 males and 196 females) between the ages of 1 day and 100 years (mean age 35.93 ± 24.15), and including 25 victims of hangings, were examined to reveal the pattern of age-related change and the types of injury that occurred. Thyroid cartilage anomalies likely to cause confusion and be misinterpreted as trauma-related are documented. Angulation of the thyroid cartilage horns was found to change with age, and it is suggested this may be a significant factor in traumatic neck injury. Unlike in previous reports, the average age of hanging victims with fractures to the thyroid cartilage was 34 years. The base of the superior horn was the most common fracture site and in 50 % of hanging cases was associated with a ligature positioned on the thyrohyoid membrane or thyroid lamina. Although an age-related relationship exists it was not possible to establish narrow age-prediction ranges from calcification of the thyroid cartilage.